From Gineipaedia, the Legend of Galactic Heroes wiki

Baron Scheidt (Japanese: シャイド) was the nephew of Duke Otho von Braunschweig and the ruler of the planet Westerland. He was killed by his subjects following their harsh treatment and the answering of protests with military force. His death infuriated Braunschweig past the point of reason causing him to order the nuclear attack that resulted the infamous Westerland Massacre, an event that would seal the Lippstadt League's fate.